1. Field of the Invention
The invention relates to a light-emitting device.
2. Description of the Related Art
An optical semiconductor device using a surface mount ceramic package is known which has electrode terminal solder pads and dummy solder pads on a mounting surface of the ceramic package (see e.g., JP-A-2010-10437).
Since the optical semiconductor device of JP-A-2010-10437 has the dummy solder pads, it is possible to ensure positional stability during the reflow soldering process and thermal fatigue life of the soldered portion of the electrode terminal solder pads also can be improved.
Also, a surface mounted optical semiconductor device is known which has a level difference on a back surface of the package on which a lead is exposed (see e.g., JP-A-2010-199253).
In the optical semiconductor device of JP-A-2010-199253, solder creeps up along a recessed portion of the level difference of the lead and forms solder fillets during the reflow soldering process at the time of side-view mounting the optical semiconductor device. In this case, solder fillets are formed in one direction unlike when solder creeps up along a raised portion of the lead. Therefore, it is possible to stabilize the position of the terminals with respect to the mounting substrate while preventing the faulty mounting.